Is it possible to map specific fields from one CDT to another within an expressi

Question

Is it possible to map specific fields from one CDT to another within an expression rule? So far I have been unsuccessful. Code is below - any suggestion would be greatly appreciated!

with(
cacData : rule!CAC_getExceptionByIDAndNotStatus(ri!crsExceptionID, "Cleared"),
crsData: rule!CAC_getCRSExceptionCollateralByActivityIdAndCollateralCode(pv!cacData.activityID, pv!cacData.typecode),

cacData.crsExceptionID : crsData.ActivityId_Int,
cacData.description : crsData.Description_txt,
cacData.exceptionType : crsData.Type_Txt,
cacData.crsStatus : crsData.Status_Txt,
cacData.deadlineDate : crsData.DeadlineDate_Dte,
cacData.addedDate : crsData.AddedDate_Dte,
cacData.descriptionLine1: crsData.Description1_Txt,
cacData.descriptionLine2: crsData.Description2_Txt,
cacData.recordcd : crsData.RecordCd_Txt,
cacData.loanNumber : crsData.LoanNbr_Int,
cacData.customerNumber : toInteger(crsData.Customer_Dec),
cacData.tiedTable : crsData.TiedTable_Txt,
ca...

sikhivahans · Answer

@ashleyb If I understand your question correctly, following snippet resolves your query:

with(
\tlocal!cacData : rule!CAC_getExceptionByIDAndNotStatus(ri!crsExceptionID, "Cleared"),
\tlocal!crsData: rule!CAC_getCRSExceptionCollateralByActivityIdAndCollateralCode(pv!cacData.activityID, pv!cacData.typecode),
\t
\t/*Assuming that local!cacData has a single value*/
\tlocal!newCacData:type!cacData(
\ tcrsExceptionID:local!cacData.ActivityId_Int,
\ tdescription: local!crsData.Description_txt,
\ texceptionType: local!crsData.Type_Txt,
\ tcrsStatus: local!crsData.Status_Txt,
\ t... and so on
\t),
\t
\t/*Assuming that local!cacData has multiple values*/
\tlocal!newCacData:apply(
\ ttype!cacData(
\ tcrsExceptionID:,
\ tdescription: _ ,
\ texceptionType: _,
\ tcrsStatus: _,
\ t... and so on
\ t),
\ tmerge(
\ tlocal!cacData.ActivityId_Int,
\ tlocal!crsData.Description_txt,
\ tlocal!crsData.Type_Txt,
\ tlocal!crsData.Status_Txt
\ t...and so on
\ t)
\t),
\ttodatasubset(local!newCacData,topgainginfo(1,-1))
)

Not sure why there is local as well as process variable for cacData, but you could use the PV as long as you place the above content in the process model directly, else you may pass the PV as an rule input to the rule in which above contents are encapsulated.

sureshg57 · Answer

HI ashleyb 
 Yes it can be done. 
 But by looking at your code, I would suggest you to pass the variables in to the expression rather than accessing the parent variable with out passing as a parameter. This is the best practice and it give more readability and maintainability to the code. 
 Once you have the first two CDTs populated using the rules construct a new CDT using 'type' construct and map the desired value and return the newly created CDT from the expression. 
 for ex: 
 local!firstCDT : rule!CAC_getExceptionByIDAndNotStatus(ri!crsExceptionID, "Cleared"),
local!secondCDT : rule!CAC_getCRSExceptionCollateralByActivityIdAndCollateralCode(ri!cacData.activityID, ri!cacData.typecode),

local!returnCDT: 'type!{yourcdtnamespace}yourCDTname'(firstEle : local!firstCDT.ActivityId_Int,secondElement: local!secondCDT.LoanNbr_Int), 
 Regards 
 Suresh